In the prior art for suppressing layer interferences it is known from U.S. Pat. No. 7,626,241 B1 to reduce thin film interference ripples in coated sensor surfaces through variably adjusted thicknesses in different regions of the thin film. Due to the integration of the sensors in integrated circuits with embedded signal processing and intermediate metal layers, the silicon dioxide layer for passivation of the silicon is relatively thick and is therefore responsible for the interference ripples. Due to the jump in the refractive index between the Si sensor and the passivation layer, the latter is applied over the light-sensitive sensor surface with two different thicknesses so that the interferences ideally average out.
This has the disadvantage that these partial differences in thickness must be produced for each light-sensitive surface directly in the wafer fabrication process which is already complex.